A method for preparing all-solid-state photonic crystal fiber preform by extrusion by aligning the center of the first jacking end of the first jacking rod with the center of the core outlet mold. The adverse effect on this part of extruded core glass by oxygen or other impurities in air during the extrusion out of the core outlets can be avoided. The defects on the core glass surface and the cladding glass surface can be effectively removed, and the purity and quality of the core component in the obtained fiber preform can be improved.

A shaped tube (50,51) for use as a component in the fabrication of an antiresonant hollow core optical fibre, the shaped tube having a side wall with a transverse cross-sectional shape comprising a number of major curved portions (52) alternating with the same number of minor substantially straight portions (54), each curved portion (52) having an inwardly curving shape, and each straight portion (54) being equidistant from a central longitudinal axis of the shaped tube (50,51).

Certain exemplary embodiments can provide a system, machine, device, manufacture, circuit, and/or composition of matter, and/or a method for activities, that can comprise and/or relate to, a polarization-maintaining photonic crystal fiber comprising an elongated guiding core and/or an elongated photonic crystal cladding surrounding the core, the cladding defining a plurality of holes.

A shaped tube (50,51) for use as a component in the fabrication of an antiresonant hollow core optical fibre, the shaped tube having a side wall with a transverse cross-sectional shape comprising a number of major curved portions (52) alternating with the same number of minor substantially straight portions (54), each curved portion (52) having an inwardly curving shape, and each straight portion (54) being equidistant from a central longitudinal axis of the shaped tube (50,51).

A molding device and a molding method for an optical fiber preform are provided. The molding device includes a rotating mechanism, an extrusion mechanism, and a cylinder mold that is of a cylindrical structure with two ends each having an opening. After a hollow cladding sleeve is obtained by rotating the cylinder mold through the rotating mechanism, a molten core glass is then reversely extruded into the cladding sleeve in the cylinder mold from bottom to top by the extrusion mechanism to prepare the optical fiber preform.

Certain exemplary embodiments can provide a system, machine, device, manufacture, circuit, and/or composition of matter, and/or a method for activities, that can comprise and/or relate to, a polarization-maintaining photonic crystal fiber comprising an elongated guiding core and/or an elongated photonic crystal cladding surrounding the core, the cladding defining a plurality of holes.

The present invention discloses a method for preparing all-solid-state photonic crystal fiber preform by extrusion. Firstly, aligning the center of the first jacking end of the first jacking rod with the center of the core outlet mold. The adverse effect on this part of extruded core glass by oxygen or other impurities in air during the extrusion out of the core outlets can be avoided. The defects on the core glass surface and the cladding glass surface can be effectively removed, and the purity and quality of the core component in the obtained fiber preform can be improved.

A hollow-core fiber with a single layer of robust anti-resonant optical arches is disclosed, which is designed and made of infrared soft glass and allows the transmission of mid- to long-infrared wavelengths (1-15 microns). Each curved arch is solidly attached at two locations on the outer solid region surface and together the arches define the core diameter. The thickness and spacing between the arches are selected to minimize the fiber transmission loss <1 dB/m at wavelengths in the mid- to long-infrared where the infrared soft glass has high absorption >30 dB/m. A hollow-core preform with anti-resonant arches is made by extrusion of infrared soft glasses through a die specifically designed to produce the hollow-core fiber with anti-resonant arches.

A hollow-core fiber with a single layer of robust anti-resonant optical arches is disclosed, which is designed and made of infrared soft glass and allows the transmission of mid- to long-infrared wavelengths (1-15 microns). Each curved arch is solidly attached at two locations on the outer solid region surface and together the arches define the core diameter. The thickness and spacing between the arches are selected to minimize the fiber transmission loss <1 dB/m at wavelengths in the mid- to long-infrared where the infrared soft glass has high absorption >30 dB/m. A hollow-core preform with anti-resonant arches is made by extrusion of infrared soft glasses through a die specifically designed to produce the hollow-core fiber with anti-resonant arches.

A molding device and a molding method for an optical fiber preform are provided. The molding device includes a rotating mechanism, an extrusion mechanism, and a cylinder mold that is of a cylindrical structure with two ends each having an opening. After a hollow cladding sleeve is obtained by rotating the cylinder mold through the rotating mechanism, a molten core glass is then reversely extruded into the cladding sleeve in the cylinder mold from bottom to top by the extrusion mechanism to prepare the optical fiber preform.